Method and apparatus for accessing internet service in a mobile communication network

ABSTRACT

Internet service in a digital mobile communication network by means of short message service. The short message service center is connected to the Internet network and uses the HTML, HTTP, and TCP/IP Internet network protocols. Short messages are transferred between the service center and mobile stations. The user submits to the service center a short message containing an identifier of a WWW servicer via the Internet network, receives the WWW page and stores it. The relevant part, which maybe identified by a predetermined criterion, common to all subscribers, or based on a criterion received from the mobile station, such as a keyword, is separated from the WWW page and sent to the mobile station in a short message. The mobile station processes the received message and displays it to the user.

This application is the national phase of international applicationPCT/F197/00547 filed Sep. 15, 1997 which designated the U.S.

BACKGROUND OF THE INVENTION

The invention relates generally to digital mobile communication systemsand more particularly to providing data service in a mobilecommunication system.

Mobile communication systems refer, in general, to differenttelecommunication systems providing personal wireless data transmissionwhile subscribers roam the system area. A typical mobile communicationsystem is the public land mobile network PLMN.

Besides conventional speech transmission, digital mobile communicationsystems provide a plurality of other services: short messages,facsimiles, data transmission, etc. Of these, the data transmissionservice, in particular, provides a mobile subscriber a chance ofwireless access to nearly all data services of fixed networks.

The use of the Internet data network in fixed networks has increasedvery rapidly. As is well known, the Internet network actually comprisesa large number of smaller interconnected networks. Data transmission inInternet is packet-switched in accordance with the TCP/IP protocol(Transmission Control Protocol/Internet Protocol). The growingpopularity of Internet is primarily due to a system called World WideWeb (WWW). The WWW system consists of servers in the Internet networkand customer programs used by these servers, called WWW browsers. Theinformation in the WWW servers is arranged into pages which are thebasic units of the WWW technique, as whole pages are always transferredbetween a server and a browser. In addition to text, the page may alsocontain graphics and various other file types, such as voice and video.The pages used by the WWW technique are described with the HTML language(Hyper Text Mark-up Language). Information on text format, graphics,etc. is coded among the actual text contents by HTML tags. The browserprogram uses these tags to give a WWW page the desired format.

There is a connection between a WWW server and a user only during thetransfer of a WWW page to a user. This means that when requesting a WWWpage, a user sends a transfer request to a WWW server which sends therequested page back via the line. Transfer requests and WWW pages aretransferred by the HTTP protocol (Hyper Text Transfer Protocol). Thereceiver's browser program restores the WWW page received into the rightform in accordance with the HTML language. A transferred WWW page isstored in the memory of the user's computer, the user being able tobrowse the page on his/her own screen. The addressing format of theInternet WWW servers is URL (Uniform Resource Locator).

Through the data transmission services of mobile communication systems,the numerous information sources of the Internet network are, inprinciple, available to mobile subscribers, too. However, the use ofdata transmission services typically requires a mobile station providedwith data transmission properties, and a computer connected thereto. Atpresent, mobile stations including an integrated computer, such as theNokia Communicator, are available. However, these are relativelyexpensive alternatives and hence not suitable to occasional usage by anordinary mobile subscriber.

The Internet network, however, offers numerous information sources whichcould be useful to an ordinary user, too. These could include e.g.flight, train, bus schedules, weather and traffic reports, telephonenumber and address information etc. At present, most of these servicesare free of charge and available to everybody. Internet is also commonlyused in companies for internal services. Thus it would be advantageousto render the various information sources offered by Internet availableto users of mobile stations without any data transmission facilities.

DISCLOSURE OF THE INVENTION

It is an object of the present invention to retrieve information fromthe Internet network without the need to use the data transmissionservice of a mobile communication network, or a browser program of WorldWide Web pages in a mobile equipment.

This is achieved with a method of accessing a data network in a digitalmobile communication system providing short message service. The methodis characterized by the steps of

transferring a short message including an identifier indicating a WordWide Web (WWW) page in the Internet network from a mobile station overthe mobile communication network to a short message service centrehaving access to the Internet network either directly or via a computerin connection with said service centre,

communicating towards the Internet network using the protocols of theInternet network and retrieving said WWW page indicated by said shortmessage, or a part of said WWW page,

converting a relevant part of the contents of said WWW page into a shortmessage,

sending the short message over the mobile communication network to themobile station,

displaying the contents of the short message on the display of themobile station.

The invention also relates to a short message service centre for adigital mobile communication system providing short message service, theshort message service centre comprising: first means for accessing amobile communication network for transferring short messages between theshort message service centre and mobile stations, and second means foraccessing a data network. The service centre is characterized in that

said data network is the Internet network,

said second means comprise means for retrieving Word Wide Web (WWW)pages from the Internet network using the protocols of the Internetnetwork in response to a short message sent by a mobile station, themessage either directly or indirectly indicating said WWW page, and that

the short message service centre further comprises means for convertingthe relevant part of the contents of the WWW page into a short messageto be sent to the mobile station via the mobile communication network.

The invention further relates to an equipment for connecting the shortmessage service centre of a digital mobile communication system to adata network. The equipment is characterized in that said data networkis the Internet network, and that the equipment comprises

means for retrieving Word Wide Web (WWW) pages from the Internet networkusing the protocols of the Internet network in response to a shortmessage sent by a mobile station to the short message service centre,the message indicating said WWW page, and

means for converting the relevant part of the contents of the WWW pageinto a short message to be sent to the mobile station via the shortmessage service centre and the mobile communication network.

In the present invention, a mobile subscriber searches the Internet WWWpages for information by the aid of the short message service of themobile communication network. For this purpose the short message servicecentre or other equipment in connection thereto is provided with accessto the Internet network and uses HTML, HTTP, and TCP/IP protocolstowards Internet. In addition, the short message service centre isconnected to a mobile communication system in the usual manner such thatshort messages are transferred between the short message service centreand mobile stations in a manner defined for the mobile communicationsystem.

When requiring information from an Internet WWW page, a mobile usersends to the service centre a short message including an identifier fordirectly or indirectly indicating said WWW page. Direct indicationincludes e.g. the address of the WWW page, URL. URL addresses are oftenquite long and hard to remember, and it is not always useful to transferthem to the service centre in a short message. In an embodiment of theinvention, a mobile station sends, instead of an address, a shortkeyword indirectly indicating the desired WWW page. The short messageservice centre or said other equipment comprises a table for linking thekeywords and the addresses of WWW pages.

Having received a short message, the short message centre or said otherequipment contacts the desired WWW server via Internet, receivestherefrom the WWW page and stores it.

The length of a short message is limited, e.g. 160 characters, whereas aWWW page may comprise an enormous amount of information. This is why inthe primary embodiment of the invention the short message service centreor said other equipment is provided with means for converting or“compressing” the WWW page received from Internet into a form suitableto the transmission capacity of the short message service of the mobilecommunication system. In an embodiment of the invention, the shortmessage service centre or said other equipment separates or “filters”only the relevant part of a WWW page and sends it in a short message tothe mobile station. The part of a WWW page containing relevantinformation may be identified by a predetermined fixed criterion, commonto all subscribers, or it may be based on a criterion received from themobile station, such as a password. This password may be included in theshort message sent by the mobile station, together with the identifierof the WWW page. The short message service centre or said otherequipment searches the WWW page received and stored for the pointincluding said relevant information and places it in a short message.The length of the text to be placed in a short message can be limitede.g. by character strings used on WWW pages, such as HTML tags. In thisway a paragraph of a WWW page including the desired information, forexample, may be placed in the s short message.

The mobile station receives and processes the “Internet” short messagereceived from the short message centre as a normal short message. Theshort message may be displayed on the mobile station screen en in theusual manner. Thus no data transmission properties or WWW browsers arerequired in the mobile station for the use of the Internet WWW service.The only technical requirement is that the mobile station be providedwith a conventional short message facility. In addition, the usertypically has to have a subscriber contract with a short message servicee centre supporting the service according to the invention.

The invention does not require any changes in the mobile e communicationnetwork, either, but a short message centre provided with the newproperties required by the invention, or with other equipment comprisingthem, may be connected to the mobile communication network in a standardmanner.

Thus the invention may be used to easily provide existing mobilecommunication networks with an Internet net work access, and to offer itto mobile station already in the network and comprising a short messagefacility. In principle, the mobile station user does not even have to beaware of the fact that the information required is retrieved fromInternet. The user simply sends an information inquiry in the form of ashort message t o the short message service centre and obtains thedesired information in a reply message.

BRIEF DESCRIPTION OF THE DRAWINGS

The primary embodiments of the invention are described below withreference to the attached drawings, in which

FIG. 1 is a system diagram illustrating how a mobile communicationnetwork and the Internet network a re interconnect ed by a short messageservice centre according t o the invention,

FIGS. 2 and 3 are signalling diagrams illustrating the transfer of an MOshort message and an MT short message, respectively,

FIG. 4 is a block diagram of a service centre according to a primaryembodiment of the invention,

FIG. 5 is a conversion table stored in a data base 43,

FIG. 6 shows a mobile telephone with the contents of a short messagedisplayed on the screen.

PREFERRED EMBODIMENTS OF THE INVENTION

The present invention may be applied to all mobile communication systemssupporting circuit switched speech and data services and using shortmessage service. In the present application, short message servicerefers to the transfer of a short text message between a mobile stationand a special short message service unit without the need to set up apoint-to-point connection. This is why the transfer of a short messagemay take place even when in the mobile station there is a speech or datacall in progress on a circuit-switched point-to-point connection. Shortmessage transfer is limited to one message, i.e. the transfer of onemessage constitutes the whole transaction. Thus, short message serviceis totally different from packet-switched data transmission.

In the following the invention will be described in connection with thedigital GSM (Global System for Mobile Communication). Regarding theinvention, the operation and structure of the mobile communicationsystem are not relevant, and hence they are described only to a degreethat will assist in comprehending short message service. As to a moreprecise description of the GSM system, reference in made to the GSMrecommendations and the publication “The GSM System for MobileCommunications”, M. Mouly & M. Pautet, Palaiseau, France, 1992,ISBN:2-9507190-0-7.

Referring to FIG. 1, a mobile switching centre MSC switches incoming andoutgoing calls. It also performs tasks typical of mobile telephonetraffic, such as subscriber location management, in co-operation withthe network subscriber registers VLR and HLR. The HLR is a subscriber'shome register for permanent storage of subscriber data. The visitorlocation register VLR is a local register to which the subscriber datais copied from the HLR when a mobile subscriber visits the area of theVLR. Mobile stations MS communicate with the centre MSC via base stationsystems BSS. The BSS consists of a base station controller BSC and basestations BTS, i.e. fixed radio transceivers via which the mobilestations MS communicate with the mobile communication network over theradio path.

The European Telecommunications Standards Institute (ETSI) standard GSM03.40 describes the point-to-point (PP) short message service (SMS) ofthe GSM system. The SMS of the GSM network offers means for transferringshort messages with limited length (160 ASCII characters) between mobilestations MS and a short message service centre SC 10 which is outsidethe GSM network 11. Mobile originated (MO) and mobile terminated (MT)short message transmissions are defined as separate services. MO shortmessages are transferred from the MS to the service centre SC. Theseshort message may be destined for other mobile station users or forsubscribers on a fixed network. MT short messages are transferred fromthe service centre SC to the MS. These short messages may have arrivedat the service centre SC from other mobile station users or from othersources. The protocol employed between the SC and the MS is called SM-TP(Short Message Transport Protocol).

The service centre SC is connected to the mobile communication networkvia a certain MSC, called the SMS-Gateway MSC when MT short messages areinvolved, and SMS-Interworking MSC when MO short messages are involved.The present application uses a common name SMS-Gateway (SMS-GW). TheSMS-GW relays short messages between a MS and the SC and performs theHLR (and VLR) inquiries needed for an MT message in a call. The servicecentre SC is given a dedicated ISDN number in the number space of theGSM network, and the MS uses the ISDN number for addressing a shortmessage to the SC.

In the following the transfer of MO and MT short messages will bebriefly described with reference to FIGS. 2 and 3.

When wishing to send a short message (FIG. 2), a user has to key in atleast its contents and the ISDN number of the service centre SC thatwill process the message. Sending a short message requires that asignalling connection (reservation of radio resources (RR)) be set upbetween the mobile station and the serving MSC, if such a connectiondoes not yet exist. This is carried out in the same way as for othercommunication. In order to separate a short message from potential othersignalling at the link layer, a link identifier SAPI 3 (Service AccessPoint Identifier) is applied to it, whereas the SAPI of the signallingis 0. An MO short message, called an SM-TP SMS-SUBMIT message, is sentvia the serving MSC and SMS-GW (on the basis of the ISDN number) to theright service centre SC.

Transmission of an MT short message is somewhat more complicated (FIG.3). The service centre initiates short message transmission by sendingto the SMS-GW a message SM-TP SMS-DELIVER containing at least thecontents of the short message and the MSISDN number of the addressedmobile subscriber. The SMS-GW derives the subscriber's HLR address fromthe MSISDN number and inquires of the HLR about routing information bythe message MAP/C SEND ROUTING INFO FOR SMS. HLR provides the routinginformation (=the address of the serving MSC) by the message MAP/C SENDROUTING INFO FOR SMS RESULT (possibly first after making a supplementaryinquiry to the VLR). The SMS-GW then sends a short message, MAP/HFORWARD SHORT MESSAGE, to the serving MSC. The MSC sets up a signallingconnection if it has not yet been set up, and sends to the MS a shortmessage called SM-TP SMS DELIVER. The MS receives and stores the shortmessage and alerts the user.

It should be noted that, as regards the invention, it is insignificanthow the short message service support has been implemented in the mobilecommunication system. In the GSM system, for example, the invention isapplicable to existing networks supporting short message service. Anexample of such a network is the GSM network of Radiolinja Oy inFinland. The mobile station may also be any kind of mobile stationsupporting short message service. An example is the Nokia 2110 GSM.

In the present invention the service centre SC is connected to theInternet network 12 such that it can be used as a gateway between theGSM network and the Internet network. The interface between the shortmessage centre SC and the SC centre may be a direct interface, or the SCmay be in connection with a separate computer equipment having access tothe Internet network 12. Such a separate equipment is illustrated by aCPU 14 in FIG. 14.

In this way the invention SC brings the information sources of theInternet network 12 to the use of mobile subscribers via short messageservice. A large number of users, local networks and servers, of whichFIG. 1 shows only three WWW servers 13A, 13B, and 13C, are connected tothe Internet network 12.

The block diagram of FIG. 4 shows an example of a service centre SCaccording to the invention. The interface 41 between the GSM network andthe service centre SC maybe similar to that in present short messageservice centres.

A basic element in present short message service centres SC (incomputers) is that they can be connected to data networks, a propertywhich may also be utilized at the physical level of Internetconnections. The service centre SC uses HTTP and HTML protocols towardsthe Internet network 12. The HTTP protocol again uses TCP/IP interfaces.WWW server and customer programs usable in a service centre computer(computers) SC in retrieving WWW pages according to the HTP and HTMLprotocols from the Internet network are commercially available fordifferent operating systems (such as Unix). In FIG. 4, an Internetinterface block 42 represents these Internet-specific operations of aservice centre SC.

A conversion and control unit 40 controls the retrievals of WWW pagesvia the Internet interface 42 and the transmission and reception ofshort messages via the GSM interface 41. The control unit 40 converts ashort message received by the GSM interface into a WWW page request tobe carried out via the Internet interface 42. Correspondingly, thecontrol unit 40 filters the relevant part of the retrieved WWW page andplaces it as the contents of the short message which is sent via the GSMinterface to the MS. In addition the service centre comprises a database 43 for storing retrieved WWW pages and various parameters,conversion tables etc. required by the control unit.

If the service centre SC is connected to the Internet network by meansof a separate computer equipment CPU14, the operational blocks of FIG. 4may be decentralized between the SC and the CPU14. For example, the GSMinterface 41 may be a normal short message service centre SC, whereasthe control unit 40, the Internet interface 42, and the memory 43 arelocated in the separate equipment CPU14. This is an advantageousaltemative particularly when the service according to the invention isintroduced into old short message service centres.

When requiring information from an Internet WWW page, a mobile usersubmits a short message addressed (ISDN number) to the service centreSC, the message containing an identifier for directly or indirectlyindicating said WWW page. Direct indication contains e.g. the WWW pageaddress, URL. Examples of URL addresses are http://www.nokia.com andhttp://www.uspto.gov/. In an embodiment of the invention, instead of anURL address, the user keys in a short keyword in the short messageindirectly indicating the desired WWW page. The data base 43 of theservice centre SC comprises a table for linking keywords and WWW pageaddresses. FIG. 5 shows an example of such a table. For example, whenrequiring information on bus schedules from a WWW page whose URL ishttp://www.bus.com/timetable, the user sends the code BUS in the shortmessage to the service centre SC.

A short message is transferred to a service centre SC as a normal MOshort message. Having received the short message, the GSM interface unit41 forwards the contents to the control unit 40. On the basis of thekeyword, the control unit 40 retrieves the URL address from the table.The control unit 40 then preferably checks if said WWW page has beenretrieved previously and is stored in the data base 43. If the data base43 does not include the page, the control unit 40 retrieves the WWW pagecorresponding to the URL address from the Internet network via theinterface 42 and stores it.

The length of a short message is limited, e.g. 160 characters, whereas aWWW page may contain an enormous amount of information. In most casesthe user is interested only in certain information that is hidden amongother data. Therefore, in a primary embodiment of the invention, thecontrol unit 40 separates or “filters” only the relevant part of the WWWpage and sends it in a short message to the mobile station.

The HTML language depicting WWW pages consists of tags entered in thetext within angle brackets <>. Such tags are e.g. the paragraph tag <P>,the page header tag <TITLE>, change of paragraph <P>or <BR>, a list<UL>, etc. These HTML tags appearing on WWW pages may be used to definethe size of the text portion to be placed in a short message. Otherarbitrary character strings may also be used alternatively or inaddition. In this way e.g a paragraph (the text between two <P>tags) ofa WWW page including the desired relevant information may be placed in ashort message. By using standard HTML tags as templates, all current WWWinformation is rendered available to the short message service withoutany changes or with slight changes to WWW pages. In the invention, theHTML text is converted into readable format before transmission. Thetext is also compressed by omitting unnecessary white fields from thetext. The HTML tables are converted into separate paragraphs.

The part of a WWW page containing relevant information may be identifiedby a predetermined fixed criterion, common to all subscribers, or it maybe based on a criterion received from the mobile station, such as akeyword.

For example, a short message including the keyword WEATHER, causes a WWWpage containing weather reports to be retrieved from Internet.

When using a fixed criterion, a paragraph dealing with tomorrow'sweather, for example, may be separated from this page.

When using a keyword or other search text, the WWW page is searched forthe corresponding text between predetermined HTML tags. Thecorresponding text block is then returned to the MS in a short message(usually converted from the HTML language into a readable language). Amobile user may include the keyword in a short message requestinginformation from the WWW page.

A MS may send the inquiry BUS 65A, for example, in a short message. Thecontrol unit of the service centre SC retrieves from the data base theURL http://www.bus.com/timetable corresponding to the code BUS. Thecontrol unit then checks if the WWW page corresponding to the URL existsin the data base. If not, the control unit 43 retrieves said WWW pagefrom Internet 12 via the interface 42 and stores it in the data base 43.A stored WWW page may have e.g. the following appearance:

<BODY>

<P>Bus company Limited Timetable </P>,

<P>64:14.45 15.10 15.30 15.55 </P>

<P>65A:15.45 16.20 17.30 </P>

</BODY>

<HTML>

The control unit 40 searches the WWW page for the paragraph includingthe keyword 65A and deletes superfluous information. In this case theshort message to be sent to the mobile station MS would look like this:

65A: 15.45 16.20 17.30

The control unit 40 sends this short message via the GSM interface 41 tothe GSM network where it is relayed to the MS in the same manner asdescribed in FIG. 3. The MS receives and processes the “Internet” shortmessage received from the short message centre as a normal shortmessage. The short message may be displayed on the mobile station screenin the usual manner, as illustrated in FIG. 6.

Another way to proceed is to use WWW pages with inquiry scripts, i.e.inquiry expressions drawn up in a command language. This means that itis the WWW server maintaining the WWW page that filters the relevantpart of the WWW page according to the inquiry it received and returnsthe relevant part as a WWW page to the service centre SC. The servicecentre has to be aware of the inquiry format of each WWW page (service).In addition, the mobile subscriber should be aware of all inquirykeywords. With this type of functionality the searches would, however,be more accurate.

For example, in response to a short message including the abovedescribed inquiry BUS 65A, the service centre SC could send to the WWWserver of the WWW page http://www.bus.com/timetable the inquiryhttp://www.bus.com/timetable?bus=65A. According to the inquiryparameters and the inquiry script of the WWW page, the WWW servercreates a reply which is sent in HTML format (a WWW page) via Internet12 back to the service centre SC. The reply from the WWW server couldlook like this:

<BODY>

Timetable for bus 65A:

15.45 16.20 17.30

</BODY>

<HTML>

The control unit 40 of the service centre SC converts and cleans up thereply into readable text format, the final short message looking likethis:

Timetable for bus 65A: 15.45 16.20 17.30

In the above described cases the control unit 40 sends only the relevantpart of a WWW page in a short message. In an embodiment of theinvention, the control unit has, however, an optional operation modewherein it does not search for the relevant part of a WWW page, butinstead sends the whole page, as a cleaned-up version: the HTML text isconverted into readable format and the superfluous empty fields aredeleted in order to compress the text and reduce message size. This issimilar to the procedure performed above in the last example.

In still another embodiment of the invention the control unit 40 has anoptional operation mode wherein the contents of a WWW page are sent inHTML format in a short message. Only the superfluous empty fields aredeleted to reduce the size of the short message.

In the above the invention has been illustrated by means of primaryembodiments. The invention is not, however, limited to the solutionspresented, but can be varied within the scope and spirit of the attachedclaims.

What is claimed is:
 1. A method for accessing a data network in adigital mobile communication system providing short message service, themethod comprising: transferring a first short message including at leastone keyword indicating a Word Wide Web (WWW) page in the Internetnetwork from a mobile station over the mobile communication network to ashort message service centre having access to the Internet network inconnection with said service centre, converting the keyword into theUniform Resource Locator (URL) address of the WWW page, communicatingtowards the Internet network using the protocols of the Internet networkand retrieving said WWW page, or a part of said WWW page based on saidconverted URL address, converting a relevant part of the contents ofsaid WWW page into a second short message, sending the second shortmessage over the mobile communication network to the mobile station,displaying the contents of the second short message on the display ofthe mobile station.
 2. A method as claimed in claim 1, wherein theconverting of the keyword into the Uniform Resource Locator (URL)address of the WWW page is performed by a keyword/URL conversion table.3. A method as claimed in claim 1, wherein said conversion of the WWWpage into the second short message comprises identifying said relevantpart on the WWW page by a search criterion received in said first shortmessage from the mobile station.
 4. A method as claimed in claim 3,wherein said search criterion comprises one or more keywords.
 5. Amethod as claimed in claim 1 wherein said conversion of the WWW pageinto said first short message comprises separating said relevant textpart from the WWW page by a predetermined character string.
 6. A methodas claimed in claim 5, wherein said character string is a Hyper TextMark-Up Language (HTML) tag in the WWW page.
 7. A method as claimed inclaim 6, wherein the whole of said text and the HTML tag correspondingthereto are some of the following: paragraph and HTML tag <P>; pageheader and HTML tag <TITLE>; paragraph change and HTML tag <P> or <13R>;and a list and HTML tag <UL>.
 8. A method as claimed in claim 1, furthercomprising: sending a search criterion to the WWW page WWW server in theInternet network as indicated by the first short message, separatingsaid relevant part of said WWW page in the WWW server on the basis ofthe search criterion, returning a modified WWW page from said WWW serverin response, the page containing only said relevant part, converting theWWW page into the second short message and sending the second shortmessage to the mobile station.
 9. A method as claimed in claim 1,wherein said conversion of the WWW page into the second short messagecomprises optimizing the length of the second short message by deletingsuperfluous empty are as from said relevant part.
 10. A method asclaimed in claim 1, wherein said conversion of the WWW page into thesecond short message comprises converting said relevant part from HTMLformat into normal text format.
 11. A method as claimed in claim 1,wherein said communication with the Internet network and said conversionof the WWW page into a short message is carried out in said separatecomputer connected with the short message service centre.
 12. A shortmessage service centre for a digital mobile communication systemproviding short message service, the short message service centrecomprising: first device configured to access a mobile communicationnetwork for transferring short messages between the short messageservice centre and mobile stations, and second device configured toaccess an Internet network, said second including means for retrievingWord Wide Web (WWW) pages from the Internet network using the protocolsof the Internet network in response to a first short message sent by amobile station, the first short message indicating said WWW page byusing a keyword, and the short message service centre further includinga converter for converting a relevant part of the contents of the WWWpage into a short message to be sent to the mobile station via themobile communication network.
 13. A short message service centre asclaimed in claim 12, wherein the short message service centre includesmeans for converting the keyword into Uniform Resource Locator (URL)address of the WWW page.
 14. A short message service centre as claimedin claim 12, wherein the converter includes means for identifying saidrelevant part on the WWW page by a search criterion received in saidfirst short message from the mobile station.
 15. A short message servicecentre as claimed in claim 12, wherein the converter includes means forseparating said relevant text part from the WWW page by a predeterminedcharacter string of the WWW page including a Hyper Text Mark-Up Language(HTML) tag.
 16. A short message service centre as claimed in claim 15,wherein said relevant text part and the HTML tag corresponding theretoare some of the following: paragraph and HTML tag <P>; page header andHTML tag <TITLE>; paragraph change and HTML tag <P> or <BR>; and a listand HTML tag <UL>.
 17. A short message service centre as claimed inclaim 12, wherein the converter includes means for optimizing the lengthof the short message by deleting superfluous empty areas from saidrelevant part, and for converting said relevant part from HTML formatinto normal text format.
 18. A short message service centre as claimedin claim 12, wherein said second device is located in a computercommunicating with the short message service centre.
 19. An equipmentfor connecting the short message service centre of a digital mobilecommunication system to an Internet network, the equipment comprising: afirst device for retrieving Word Wide Web (WWW) pages from the Internetnetwork using the protocols of the Internet network in response to ashort message sent by a mobile station to the short message servicecentre, the message indicating said WWW page, and a second device forconverting the relevant part of the contents of the WWW page into ashort message to be sent to the mobile station via the short messageservice centre and the mobile communication network.
 20. An equipment asclaimed in claim 19, wherein the equipment includes a computer unitcommunicating with the short message service centre and having access tothe Internet network.
 21. A method for accessing an Internet network ina digital mobile communication system, wherein the mobile communicationsystem provides a message service, the method comprising: transferring amessage including a keyword indirectly indicating a Word Wide Web (WWW)page in the Internet network from a mobile station over the mobilecommunication system to a message service centre having access to theInternet network; converting the keyword into the Uniform ResourceLocator (URL) address of the WWW page; communicating towards theInternet network using the protocols of the Internet network andretrieving said WWW page, or a part of said WWW page, on the basis ofthe URL address; converting a relevant part of the contents of said WWWpage into a message; sending the message over the mobile communicationnetwork to the mobile station; and displaying the contents of themessage on a display of the mobile station.
 22. A message service centrefor a digital mobile communication system providing a message service,the message service centre comprising: a first device configured toaccess a mobile communication network for transferring messages betweenthe message service centre and mobile stations; a second device foraccessing Internet network; a third device for storing information onthe association between keywords and the Uniform Resource Locator (JRL)addresses of WWW pages, and for converting a keyword received in amessage from a mobile station into the URL address of the WWW page; afourth device for retrieving Word Wide Web (WWW) pages from the Internetnetwork using the protocols of the Internet network on basis of the URLaddress; and a fifth device for converting the relevant part of thecontents of the WWW page into a message to be sent to the mobile stationvia the mobile communication network.
 23. A method for retrievinginformation, comprising: sending a message to a messaging service centrefrom a mobile station via a digital mobile communications system by amessaging service supported by said digital mobile communicationssystem, said message containing at least one keyword as a searchcriterion and an identifier indicating a Word Wide Web (WWW) page in theInternet network, and said messaging service having access to theInternet network; accessing a server having said WWW page via theInternet network by said messaging service centre; retrieving at leastpart of the content of said WWW page to the messaging service centre;converting, on the basis of said search criterion, relevant content ofsaid WWW page into a content format having a reduced size which can beaccommodated to by a response message; sending said response messageover said digital mobile communications system to the mobile station bythe messaging service; displaying the contents of the response messageon the display of the mobile station.
 24. A messaging service centre,comprising a first interface to a digital mobile communications systemhaving a messaging service; a second interface to an Internet network; adevice responsive to a message containing a keyword indirectlyindicating a Word Wide Web (WWW) page in the Internet network receivedfrom a mobile station via said digital mobile communications network andsaid first interface, said device converting said keyword into UniformResource Locator (URL) address and retrieving at least part of contentsof said WWW page from the Internet network via said second interfaceusing the protocols of the Internet network on the basis of said URLaddress; and a converter for converting relevant content of said WWWpage into a content format having a reduced size which is accommodatedto by a response message, and sending said response message to saidmobile station over said digital mobile communications system by meansof said messaging service.
 25. A method for retrieving informationcomprising: sending a message to a messaging service centre from amobile station via a digital mobile communications system by means of amessaging service supported by said digital mobile communications systemwithout setting up a point-to-point connection between said mobilestation and said messaging service centre, said message containing 1) atleast one keyword as a search criterion and 2) an identifier indicatinga Word Wide Web (WWW) page in the Internet network, and said messagingservice having access to the Internet network; accessing a server havingsaid WWW page via the Internet network by said messaging service centre;retrieving at least part of the content of said WWW page to themessaging service centre; converting relevant content of said WWW pageon the basis of said keyword into a content format having a reduced sizewhich is accommodated to by a response message; sending said responseover said digital mobile communications system to the mobile station bythe messaging service without setting up a point-to-point connectionbetween said mobile station and said messaging service centre;displaying the contents of the response message on the display of themobile station.
 26. A messaging service centre comprising: a firstinterface to a digital mobile communications system having a messagingservice providing messaging without need to set up a point-to-pointconnection between said mobile station and said messaging servicecentre; a second interface to an Internet network; a device responsiveto a message containing at least one keyword indirectly indicating aWord Wide Web (WWW) page in the Internet network received from a mobilestation via said digital mobile communications network and said firstinterface, said device converting said at least one keyword into aUniform Resource Locator (URL) address and retrieving at least part ofcontents of said WWW page from the Internet network on the basis of saidURL address via said second interface using the protocols of theInternet network; a converter for converting the relevant part of saidWWW page into a content format having a reduced size which isaccommodated to by a response message, said converter sending saidresponse message to said mobile station over said digital mobilecommunications.